In a liquid crystal display panel, an alignment film is applied to one or both of an array substrate and a counter substrate. A plurality of microgrooves for inducing liquid crystal molecules to align in a certain direction can be formed by rubbing a surface of the alignment film in a fixed direction. Patterns having a large height difference on the display substrate may interfere with the rubbing process. For example, the alignment layer proximal to the patterns having a large height difference may not be sufficiently rubbed, resulting in light leakage in the area, e.g., sand mura. Moreover, various liquid crystal display panels have different requirements on the thickness of the alignment film. An ultra-thin alignment film is prone to physical damages during the rubbing process. Thus, the thickness and evenness of the alignment film on the display substrate greatly affect display quality.